Better way to only update a select box if empty but leave filled boxes alone?

[lorenz-ilab]

I want to only update a select box is the select is empty or space " ". Skip if it is already selected.

//select[@id="appAuthEnrollCenter"][@selectedIndex = 0]
//select[@id="appAuthEnrollCenter"][@value = " "]
//select[@id="appAuthEnrollCenter"][@value = ""]
gives an error "Action 124 [selectedtest] No element found with the given selector skipped"

The following works for already filled in boxes. select[@id="appForSplPgm"]/option[contains(@value,"N") and @selected] but not for unselected value boxes. Since the option space is not really selected just the first item in the list.

The boxes are typically empty but sometimes "Y" which can't be changed. I need to change blanks to N and leave Y to Y.

I figured out how to do this on input box already but the combo (select) boxes are stumping me.
//input[@id="city"][@name="city"][@value=""] works fine.

I also went down the path of checking if the "Y" option is found. then later using an "Action condition" It works for Yes/No/Blank but more options it adds another line for each option.

//select[@id="appForSplPgm"]/option[contains(@value,"Y") and @selected] value Yes (value maybe not needed)
//select[@id="appForSplPgm"] value No with Action Condition
Action = //select[@id="appForSplPgm"]/option[contains(@value,"Y") and @selected] Status = "SKIPPED" Action = "Skip Action"

Ray
in the console the properties for the appAuthEnrollCenter element has a
value : space
selectedIndex = 0
Page code I added the Historcal option for discussion.

<select title="Was this application submitted by an Authorized Enrollment Center?" name="appAuthEnrollCenter" elementid="5" tabindex="5" id="appAuthEnrollCenter" size="1" class="form75" lbldesc="Was this application submitted by an Authorized Enrollment Center?" helpid="appAuthEnrollCenter" xpath="1">
 <option value=" "></option>
 <option value="N" title="No">No</option>
 <option value="Y" title="Yes">Yes</option>
 <option value="H" title="Yes Historical">Yes (Historical)</option>
 </select>

Already selected code

<select title="Was this application submitted by an Authorized Enrollment Center?" name="appAuthEnrollCenter" elementid="5" tabindex="5" id="appAuthEnrollCenter" size="1" class="form75" lbldesc="Was this application submitted by an Authorized Enrollment Center?" helpid="appAuthEnrollCenter" xpath="1">
 <option value=" "></option>
 <option value="N" title="No">No</option>
 <option value="Y" title="Yes" selected>Yes</option>
 <option value="H" title="Yes Historical">Yes (Historical)</option>
 </select>